As the author of 'The Prophecies,' Nostradamus produced 942 quatrains (four-line poems that rhyme) containing predictions for the future (until the year 3797, at least). And even though he was writing back in the 16th century, he remains a preeminent figure in the field of prognostication. Here's a look at why that is, and how Nostradamus' prophecies have affected our world.

He successfully predicted how his king would die

Nostradamus has received credit for predicting how his king, Henri II of France, would die (the prophet wrote of a pierced eye, the fatal injury that Henri received in a jousting match). And by writing that 1792 would mark "a new age," Nostradamus may have foreseen the French Revolution (1792 was the year the new Revolutionary calendar used for its starting point). Other Nostradamus lines seem to foretell the rise of Napoleon ("An emperor will be born near Italy, who will cost the Empire dear").

In more recent times, Nostradamus' work has been seen as describing the nuclear attacks on Hiroshima and Nagasaki at the end of World War II. A reference to a cruel villain terrorizing Mesopotamia was often considered to be Saddam Hussein. Even the ascension of Donald Trump to the presidency of the United States has been connected to Nostradamus' writing: "The great shameless, audacious bawler. He will be elected governor of the army" (the president is the commander-in-chief of the U.S. military).

Some of his prophecies are more open to interpretation

One thing that helps many people believe in Nostradamus' ability to peer into the future is the overall vagueness of his prophecies. It's a style he adopted deliberately, in part because he didn't want attention from the Church or other critics. It also was a way to draw readers in (besides prophecies, Nostradamus produced horoscopes and almanacs, so he understood how to appeal to the public).

The result is work so general that people can find their own meanings. For example, a prediction about the dangers of global warming can be seen in Nostradamus writing about the sea getting so hot that fish become half-cooked.

Many of his projections were based on historical events

Yet there's more than vagueness behind the popularity of Nostradamus. As noted by Peter Lemesurier, many of Nostradamus' projections into the future were based on historical events. Similarities abound in human history, so drawing on the past gives his work another layer of believability.

The warning about a dictator is clear in: "Under the feigned shadow of lifting servitude, people and city, he will usurp it himself" — there have been many tyrants in history, and likely many more to come. Nostradamus also wrote about fire, famine and floods, all of which have occurred repeatedly over the centuries.

Stéphane Gerson has noted that Nostradamus lived in a chaotic time, with wars of religion, more destructive weaponry and political realignments altering the world around him. This is reflected in his work, and it provides a connection to people who are experiencing upheaval in their own lives.

After the September 11, 2001, terrorist attacks, bookstores saw a marked upswing in sales of Nostradamus-related books — with the world feeling unsafe and the World Trade Center destroyed, some found comfort in these prophecies. (After the attack fake Nostradamus predictions of it circulated online, usually combining out-of-order Nostradamus lines with other writing.)

He didn't get everything right

Given the above, why isn't everyone studying his or her own copy of The Prophecies in order to figure out where the world is heading? Well — even though much of his work is vague — there are things Nostradamus just didn't get right.

Nostradamus didn't use a lot of dates in his prophetic writing, but 1999 is referenced: "The year one thousand nine ninety-nine seven month; From the sky shall come a great King of terror." Since that month and year passed without any such occurrence, it calls his skills into question.

His prophecies had a real-world impact

Though Nostradamus' work has its holes and weak points, it's still had a real impact. During World War II, Nazi propaganda minister Joseph Goebbels — prompted by his wife — used lines from Nostradamus to convey that the German army was destined for victory. Pamphlets were distributed across Europe with this information, in the hopes of smoothing the way for the Nazis.

Goebbels noted, "The Americans and English fall easily for that type of thing," meaning Nostradamus and the occult. But the Allied powers also recognized how useful Nostradamus could be, with Britain putting together its own pamphlets. And with the goal of increasing morale in America, MGM released several short films about Nostradamus, which made the general public aware of the seer.

Nostradamus' legacy going forward

Nostradamus wrote about the world ending in 3797, so apparently people today have a few years left. And if you believe in any of his predictions, even the most dire ones, there's still time to do what you can to avoid any unwanted outcomes.

Think of Henri II, the king whose decision to joust led to his death in 1559. If he'd been a little more cautious, and paid more attention to Nostradamus, he might have saved his own life.